Starting
Computing
The quotes
are
not printed but they indicate that some
text
is
to
be printed and they •
define exactly what
it
It
is
- everything between the opening and closing quote marks.
If
you wish
to
use
the quote symbol itself
in
a string of characters then the apostrophe
symbol can be used instead.
For
example:
PRINT
'The
quote
symboL
is
II
I
will
work and
will
print
The
quote
symboL;
s "
KEEP
SHIFT
DOWN
When using a SHIFT
key
hold
It
down while you type the other
key
so that the SHIFT
key
makes contact before the other
key
and also remains
in
contact until after the other
key
has lifted.
The same rule applies
to
the control CTRL and alternate
ALT
keys
which are used
in
conjunction with others but you
do
not need those
at
present
Type
the two simple Instructions:
4
COMMON
TYPING
ERRORS
The zero
key
IS
with
the other numeric digits
at
the top of the keyboard. and
is
slightly
thinner.
The letter
'0'
key
is
amongst the other
letters.
Be
careful
to
use the right symbol.
Similarly avoid confusion between
one,
amongst the digits, and the letter
'I'
amongst
the
letters.
CLS.II
PRINT
'HeLLo'."
Strictly speaking these constitute a computer program,
however,
it
is
the stored program
that
IS
important
in
computing. The above instructions are executed instantly
as
you type
..
" (ENTER).
Now type the program with line numbers:
10
CLS."
20 PRINT
'HELLO'."
This time nothing happens externally except that the program appears
In
the upper part
of the screen.
ThiS
means that
it
is
accepted as correct grammar or syntax.
It
conforms
to
the rules of SuperBASIC, but
it
has not
yet
been executed, merely stored.
To
make
it
work, type:
RUN_I
The distinction between direct commands for immediate action and a stored sequence
of instructions
is
discussed
in
the next chapter. For the present you can experiment with
the above ideas and
two more:
causes
an
internally stored program
to
be displayed (listed) on the screen or elsewhere.
causes
an
internally stored program
to
be deleted so that you can type
in
a
NEW
one.
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